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arXiv · 2507.19651

Cosmological observational tests in the JWST Era. I: angular size - redshift

A. A. Raikov·V. V. Tsymbal·N. Yu. Lovyagin
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Abstract

This study is devoted to the cosmological "angular size - redshift" test. An analysis is performed of the angular and linear sizes of galaxies from the new ASTRODEEP-JWST catalogue, which contains over 500,000 objects at high redshifts (up to ~20 photometrically determined and up to ~14 spectroscopically determined). For the calculations, 6 860 galaxies with reliably determined spectroscopic redshifts and 319,771 galaxies with known photometric redshifts were used. The linear sizes of galaxies were computed within the framework of two cosmological models - the standard ({\Lambda}CDM) model and one of the static models (the so-called "tired light" model). We have shown that within the framework of the {\Lambda}CDM model, a significant evolution of the linear sizes of galaxies is observed, with the rate of the evolution closely matching the rate of the cosmic expansion. In contrast, in the static model, the characteristic linear sizes of galaxies exhibit almost no evolution with increasing z.

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A. A. Raikov, V. V. Tsymbal, N. Yu. Lovyagin. 2025-07-25. Cosmological observational tests in the JWST Era. I: angular size - redshift. https://doi.org/10.1134/s1990341325600383

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